Calling while driving? Only tried it once with the Mini, while drivin slowly though.
With a touchscreen it can be trickier than the button'ed phone but still the same as you'll still have to check if the number pressed is correct. The XDA IIs wont be much different as the buttons are way too small. Nothing beats the old Nokia 3310 and 3210 for its big buttons...

Lesson: Don't Use the Phone when U drive.